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101.
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Cellulose is synthesized by the so called rosette protein complex and the catalytic subunits of this complex are the cellulose synthases (CESAs). It is thought that the rosette complexes in the primary and secondary cell walls each contains at least three different non-redundant cellulose synthases. In addition to the CESA proteins, cellulose biosynthesis almost certainly requires the action of other proteins, although few have been identified and little is known about the biochemical role of those that have been identified. One of these proteins is KORRIGAN (KOR1). Mutant analysis of this protein in Arabidopsis thaliana showed altered cellulose content in both the primary and secondary cell wall. KOR1 is thought to be required for cellulose synthesis acting as a cellulase at the plasma membrane–cell wall interface. KOR1 has recently been shown to interact with the primary cellulose synthase rosette complex however direct interaction with that of the secondary cell wall has never been demonstrated. Using various methods, both in vitro and in planta, it was shown that KOR1 interacts specifically with only two of the secondary CESA proteins. The KOR1 protein domain(s) involved in the interaction with the CESA proteins were also identified by analyzing the interaction of truncated forms of KOR1 with CESA proteins. The KOR1 transmembrane domain has shown to be required for the interaction between KOR1 and the different CESAs, as well as for higher oligomer formation of KOR1.  相似文献   
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Inappropriate left ventricular remodeling following myocardial infarction (MI) can result in subsequent severe dysfunction. In this study, we tested the hypothesis that decellularized pericardium (DP) or seeded pericardial patch with autologous adipose-derived mesenchymal stem cells (ADMSCs) could be safely used in a MI scar and could improve heart function. Twelve rabbits were randomly divided into three equal groups. Four weeks after MI induction by ligation of the left anterior descending artery in 12 rabbits, animals of G1 (n = 4) received DP patch with labeled ADMSCs. DP patch was implanted in animals of G2 (n = 4). Rabbits of G3 (n = 4) remained without any intervention after MI induction (control group). Serial examinations including echocardiography, electrocardiography (ECG), scanning electron microscopy, histology and immunohistochemistry (IHC) were performed to evaluate the efficacy of the implanted scaffolds on recovery of the infracted myocardium. The results demonstrated that left ventricular contractile function and myocardial pathological changes were significantly improved in rabbits implanted with either DP or ADMSC-seeded pericardium. However, the seeded pericardium was more effective in scar repairing 2 months after the operation, IHC staining with Desmin and CD34 and positive immunofluorescence staining verified the differentiation of ADMSCs to functional cardiomyocytes. This approach may involve the application of autologous ADMSCs seeded on pericardial patch in an attempt to regenerate a contractible myocardium in an animal model of MI.  相似文献   
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Summary Cells of wild-type Schizosacharomyces pombe exposed to UV radiation in either G1 or G2 phase show enhanced inactivation of colony-forming ability if plated in the presence of caffeine. This UV-sensitization by caffeine is abolished in both G1 and G2 phase cells by the rad1 mutation; since both caffeine and the rad1 mutation markedly reduce recombinational events, this suggests that a recombinational repair process is active in cells irradiated either in G1 or G2 phase. A prereplicative or sister chromatid exchange recombinational process appears to account for caffeine-sensitive repair of UV-damage in G2 cells (which possess at the time of radiation exposure the duplicated genome necessary for recombination), since caffeine-sensitive repair begins immediately and is completed before resumption of DNA synthesis. In contrast, since caffeine-sensitive repair of UV-damage in G1 cells displays a considerable lag and then occurs concomitantly with DNA synthesis, it appears that G1 cells must acquire a second genome in order to accomplish a caffeine-sensitive recovery process. Since a duplicated genome is required for caffeinesensitive repair, all such repair would seem to involve a recombinational mechanism. In G1 cells the process may be a post-replication recombinational mechanism. Since G2 phase cells are considerably more UV-resistant than G1 phase cells, the prereplicative recombinational process appears to be a much more efficient process for dealing with UV-induced damage than the post-replication mechanism.UV-induced mutagenesis was examined in wildtype and rad mutants using a forward mutation system. Rad mutants which show higher UV-induced mutation rates than wild-type retain UV-sensitization by caffeine (and thus presumably retain the recombinational mechanism). In contrast, rad strains which are relatively UV-immutable compared to wild-type do not possess the caffeine-sensitive UV-repair process. The recombinational process therefore may be the major pathway responsible for UV-induced mutation.AECL Reference No. 6251; NRC Publication No. 16999  相似文献   
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Probiotics and Antimicrobial Proteins - The present study was conducted to investigate the effects of probiotic and encapsulated Lactobacillus bulgaricus on hematological and immunological factors...  相似文献   
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Ergosterol as a primary metabolite and precursor of vitamin D2, is the most plentiful mycosterols in fungal cell membrane. Process optimization to increase the yield and productivity of biological products is a topic of interest. Ultrasonic waves have many applications in biotechnology, like cell disruption, and enhancement of primary and secondary metabolites production. This study disclosed an optimal condition for ultrasound-assisted production (UAP) of ergosterol from Penicillium brevicompactum MUCL 19,011 using L9 Taguchi statistical method. The intensity (IS), time of sonication (TS), treatment frequency (TF), and number of days of treatment (DT) were allocated to study the effects of ultrasound on ergosterol production. The results were analyzed using Minitab version 19. The maximum ergosterol, 11 mg/g cell dry weight (CDW), was produced on the tenth day while all factors were at a low level. The days of treatment with a contribution of 45.48% was the most significant factor for ergosterol production. For the first time, this study revealed the positive effect of ultrasound on the production of ergosterol. Ergosterol production increased 73% (4.63 mg/g CDW) after process optimization. Finally, a mathematical model of ultrasound factors with a regression coefficient of R2?=?0.978 was obtained for the ergosterol production during ultrasound treatment.

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107.
The present research focused on enhancing the production of wedelolactone through cell suspension culture (CSC) in Eclipta alba (L.) Hassk. With an aim of attaining a sustainable CSC, various plant growth regulators, elicitors and agitation speed were examined. Nodal segments of in vitro propagated plantlets induced the maximum percentage (93.47?±?0.61%) of callus inoculated on Murashige and Skoog (MS) medium fortified with picloram (2 mg L?1). The growth kinetics of CSC exhibited a sigmoid pattern with a lag phase (0–6 days), a log phase (6–18 days), a stationary phase (18–24 days) and then death phase thereafter. The highest biomass accumulation in CSC with 7.09?±?0.06 g 50 mL?1 fresh weight, 1.52?±?0.02 g 50 mL?1 dry cell weight, 1.34?±?0.01?×?106 cell mL?1 total cell count and 57.00?±?0.58% packed cell volume was obtained in the liquid MS medium supplemented with 1.5 mg L?1 picloram plus 0.5 mg L?1 kinetin at 120 rpm. High performance thin layer chromatography confirmed that yeast extract (biotic elicitor) at 150 mg L?1 accumulated more CSC biomass with 1.22-fold increase in wedelolactone (288.97?±?1.94 µg g?1 dry weight) content in comparison to the non-elicited CSC (237.78?±?0.04 µg g?1 dry weight) after 120 h of incubation. Contrastingly, methyl jasmonate (abiotic elicitor) did not alter the biomass but increased the wedelolactone content (259.32?±?1.06 µg g?1 dry weight) to an extent of 1.09-fold at 100 µM. Complete plantlet regeneration from CSC was possible on MS medium containing N6-benzyladenine (0.75 mg L?1) and abscisic acid (0.5 mg L?1). Thus, the establishment of protocol for CSC constitutes the bases for future biotechnological improvement studies in this crop.  相似文献   
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Breast cancer is the most common cancer type. In several studies, hints have been provided that there is a correlation between selenium deficiency and the incidence of breast cancer. Findings of these published reports are, however, inconsistent. This study serves as a pioneering study aiming at combining the results of studies using a meta-analytic method. A total of 16 articles published between 1980 and 2012 worldwide were selected through searching PubMed, Scopus, and Google scholar databases, and the information were analyzed using a meta-analytic method [random effects model]. I 2 statistics were used to examine heterogeneity. The information was then analyzed by STATA version 12. In this study, due to the non-uniform methods used to measure selenium concentrations, selenium levels were measured in the various subgroups in both case and control groups. There were significant correlations between selenium concentration and breast cancer [P?<?0.05]. Hence, the mean risk differentiating criteria were estimated to be 0.63 [95 % confidence interval [95% CI] 0.93 to 0.32] in serum and toenails. Subgroup analysis showed that the value in toenails was ?0.07 [95% CI ?0.16 to 0.03] and in serum ?1.04 [95% CI 1.71 to ?0.38]. In studies in which selenium concentrations were measured in serum, a significant correlation was observed between selenium concentration and breast cancer. In contrast, in studies in which selenium concentration was measured in toenails, the correlation was not significant. Therefore, the selenium concentration can be used as one predictor for breast cancer.  相似文献   
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